Several people at Valve spent the past year exploring various forms of wearable computing. The wearable effort included porting Team Fortress 2 to run in virtual reality goggles. This session will describe lessons learned from Valve's porting experience. Topics covered include an overview of what stereo support entails, rendering 2D user interface in a 90 degree field of view display, dealing with view models and other rendering shortcuts, and how mouselook can interact with head tracking in a first person shooter. In addition to the lessons that apply to Team Fortress 2, there are also several lessons that would apply to any new virtual reality game. A game designed for VR could avoid many of the issues that came up with Team Fortress 2. These topics will also be covered.